Physical and rheological parameters used for the different types of material in the numerical models. Mantle and asthenosphere follow first a dislocation creep law for dry olivine before reaching a critical threshold at a diffusion creep, grain-size sensitive flow occurs. The olivine flow laws are from Hirth and Kohlstedt (2003). We assume that the oceanic crust is dominated by a plagioclase rheology given by Shelton and Tullis (1981) with a higher activation energy to make the oceanic crust stronger. For the continental crust, feldspar and wet quartz rheology are controlled by dislocation creep laws (Rybacki et al., 2008, 2010). The general equation for creep law is  \(\dot\epsilon\ =\ A\cdot\sigma^{n}\cdot d^{-p}\cdot\exp{(-Q/RT)}\) with \(A\) the creep law pre-exponent that is determined experimentally (\(\mu m^{-p}\cdot MPa^{-R}\cdot s^{-1}\)); \(Q\) the activation energy (in \(J\cdot mol^{-1}\)); \(n\) the stress exponent; \(p\) the grain size exponent in the diffusion creep law.